Enhanced Input Validation for Asset Tokenization Contract

[timileyin-create]

Overview

This pull request introduces improved input validation mechanisms for the Real-World Asset Tokenization smart contract, focusing on strengthening security and ensuring data integrity during asset creation and transfer processes.

Validation Enhancements

1. Metadata URI Validation

• Added is-valid-metadata-uri private function to validate:
  • Non-empty URI
  • Maximum length of 256 characters
• Prevents creation of assets with invalid or excessively long metadata URIs

2. Asset ID Validation

• Implemented is-valid-asset-id private function to ensure:
  • Asset IDs are positive integers
  • Prevents usage of zero or negative asset IDs

3. Principal Validation

• Created is-valid-principal private function to:
  • Prevent contract owner from being used as a transfer recipient
  • Add an additional layer of security for ownership transfers

4. Input Parameter Checks in Functions

• create-asset:

  • Validate total supply is greater than zero
  • Confirm fractional shares are positive
  • Ensure metadata URI meets length requirements

• transfer-fractional-ownership:

  • Validate asset ID is valid
  • Check transfer recipient is a valid principal
  • Confirm asset is transferable
  • Perform compliance check before transfer

• set-compliance-status:

  • Validate asset ID
  • Confirm user principal is valid
  • Restrict function to contract owner only

Benefits

• Improved contract security
• Reduced risk of invalid asset creation
• Enhanced compliance and transfer controls
• More robust input validation

Code Changes

;; Validation functions
(define-private (is-valid-metadata-uri (uri (string-utf8 256)))
  (and 
    (> (len uri) u0)
    (<= (len uri) u256)
  )
)

(define-private (is-valid-asset-id (asset-id uint))
  (> asset-id u0)
)

(define-private (is-valid-principal (user principal))
  (not (is-eq user CONTRACT-OWNER))
)

Recommended Next Steps

• Comprehensive testing of validation functions
• Security audit focusing on input validation
• Consider adding more granular validation rules

Test Coverage

• Unit tests for each validation function
• Integration tests for asset creation and transfer
• Edge case testing for input validation

Reviewers

• Smart contract security team